"MKT Junction" on the Missouri Pacific Railroad
Above: Two photos of Tower 206 provided by the John W Barriger III National Railroad Library, both were probably taken in the late 1930s or 1940s. Below: A similar view taken in 1980 shows that the tower was rebuilt or substantially modified during the intervening years. All of these views are looking south down the I-GN tracks with the Katy veering off to the left. This junction is on the north side of town and provided a connector so that traffic on the Katy (northbound from San Antonio or westbound from Smithville) could move to the west to reach the northbound I-GN tracks upon which the Katy had rights into Austin. Southbound Katy traffic from Austin used the connector to come off the I-GN to get back to home rails.
John W Barriger III National Railroad Library photo of Tower 206, this one looking north on the Katy.
San Marcos first obtained rails when the International-Great Northern (I-GN) built through the area in 1881, part of a 234-mile track segment from Austin to Laredo. In 1887, the Missouri-Kansas-Texas (MKT, "Katy") Railroad built a 16-mile segment between Lockhart and San Marcos. The Katy was building south from Taylor through Smithville toward Houston that year, but the San Marcos - Lockhart segment remained isolated from any other part of the Katy railroad until a 36-mile Lockhart - Smithville connector was built in 1892. In 1899, a state law was passed that authorized the Katy to acquire the Sherman, Shreveport & Southern Railway between McKinney and Jefferson, but it also specified that this transaction could not be completed until the Katy tracks in San Marcos were extended 46 miles south to San Antonio. The Katy obliged, reaching San Antonio from San Marcos in 1901. Although the junction existed for decades, Tower 206 was one of the last numbered interlocker assignments in Texas. The precise date is uncertain, but it was no earlier than 1955 and no later than 1957. The specific impetus for having the interlocker entered into the Railroad Commission of Texas (RCT) control system at that time is unknown, and by the time the Tower 206 designation was authorized, the I-GN had been absorbed into the Missouri Pacific (MP) Railroad. Currently, all of these tracks are owned by Union Pacific.
Tower 206 Location Map (Bird's Eye View Facing South)
Above: This "bird's eye view" facing south shows the UP/ex-I-GN line from Austin entering San Marcos on the north side of town (at bottom). The UP/ex-MKT connector swings to the east beginning at the former site of Tower 206. The red connecting track is no longer in place preventing direct Austin-Smithville movements. From San Marcos, the MKT tracks continued all the way to San Antonio, crossing the I-GN at grade again at Tower 92. Below: The location where northbound Katy trains would switch to either Smithville or Tower 206 was called Ajax (John W Barriger National Railroad Library).
Below: Google Earth Street View of MKT Junction.